import java.util.Scanner;

/**
 * Created with Intellij IDEA.
 * Description:
 * User:Lenovo
 * Date:2024-12-07
 * Time:10:45
 */
class Solution {
    public String toLowerCase(String s) {
        if(s==null||" ".equals(s)){
            return null;
        }
        StringBuffer s2 = new StringBuffer();
        for(char a:s.toCharArray()){
            if(a>='A'&&a<='Z'){
                s2.append((char)(a+32));
            }else{
                s2.append(a);
            }
        }
        return new String(s2);
    }
}
public class Text {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Solution solution = new Solution();
        while (scanner.hasNextLine()){
            System.out.println(solution.toLowerCase(scanner.nextLine()));
        }
    }
}
